DEPENDENCY BETWEEN ROAD SURFACE GEOMETRY AND SKID RESISTANCE
Markus Weise
Last modified: 2017-02-28
Abstract
Safety and functionality are the basic requirements in road construction. To meet these requirements the qualitative and quantitative influence of the extrinsic and intrinsic factors of safety and functionality requires a detailed investigation. If the wearing course as the interface between road and tyre is considered exclusively, good skid resistance (drainage capability, friction) and acoustic behaviour constitute the most important surface characteristics. They are strongly influenced by the geometrical properties of the wearing course and may have contradictory needs. As an example, there is an overlapping domain in which the wavelength of the road texture influences both, the skid resistance and the acoustic characteristic of the wearing course. The long-term objective is to develop models for simulating all the single characteristics of the wearing course. For this purpose, every single characteristic has to be investigated and modelled independently. Then, the single approaches can prospectively be combined for artificial material design.
The focus of the current research lies on investigating the skid resistance of roads. Therefore priority is on identification of the dependency between road surface geometry and the related dimensions of skid resistance, which is still not completely explored. First, geometrical parameters of measured textures will be determined to characterise isotropic asphalt surfaces. Secondly, virtual textures on various wavelength dimensions will be generated by utilisation of the multi-scale fractal structure. Then, the conation of geometry and the appearing friction build the tribological model. This model will be transferred into a contact mechanical simulation to reproduce rubber friction numerically. Results of the simulation will be the forces in related micro-contact points. From this the rubber friction coefficient and the real contact area between tyre and road can be derived. This will give us the opportunity to specify the connection between various road surface geometries and the related dimensions of skid resistance.
Keywords
skid resistance, friction, texture analysis, tribology, simulation